Having varied credit does help with credit rating. Keeping the car loan for awhile (but not the full duration of the loan) might help with credit score.

The OP already has multiple other installment loans (car and savings secured) as well as credit card loans reported on their credit report. Installment loans continue to count toward 'varied' credit for as long as they are reported (7 years after payoff for loans with negatives; 10 years for loans that are free of negatives). In the OP's case, continuing to make payments on this loan is unlikely to 'improve' their credit score.

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